The present invention relates to production of blister packs. More particularly, the invention relates to a device for cutting single blister packs in an automatic blister packing machine.
Known blister packing machines produce automatically blister packs from a continuous band of heat-formable material. The known machines form an ordered series of blisters on the heat-formable band and fill the obtained blisters with articles. Afterwards, the blisters are closed hermetically with a sealing film, which is heat-welded to the blister band.
The blister band is cut in a subsequent shearing station, so as to obtain single blister packs, which are sent to a packaging machine.
The shearing station includes cutting means, formed substantially by a cutting punch which defines the outline of the blister to be obtained.
Consequently, such cutting means can form only one size of blister packs.
Currently, when the blister pack size is to be changed in the blister packing machines described above, it is necessary to substitute the whole group of cutting means in the shearing station.
This causes a long break in the production cycle, which results in a considerable costs increase.
Moreover, it is necessary to store in a magazine as many groups of cutting means as the blister pack sizes to be obtained.
The object of the present invention is to overcome the above problem by proposing a device for cutting blister packs, which allows to change blister size in blister packing machines easily and rapidly.
Another object of the present invention is to propose a cutting device, which is universal and can be used for any size included within the transversal dimension of the heat-formable band.
A further object of the present invention is to propose a cutting device, which is very simple to construct and functional.
The above mentioned objects are achieved, in accordance with the claims, by a device for cutting blister packs, with a selected crosswise dimension or length, from a blister band in a shearing station of a blister packing machine, with said blister band driven in a forward direction at the shearing station,
the device including:
cutting means which operate along side edges of said blister band to cut, along a cutting line, respective side strips of said blister band which go beyond said crosswise dimension, or length, of said blister packs being produced;
cut out means for cutting shaped pieces of said blister band in alignment with said cutting line of said cutting means, to define corner zones of said blister packs; and
shearing means acting crosswise on said blister band, in the region of said corner zones defined by said cut out means, for severing said blister packs;
the position of said cutting means and/or said cut out means and/or shearing means being adjustable to allow production of blister packs having different sizes.